We are proposing a placebo-controlled pilot study of selegiline versus placebo for nicotine dependent smokers (N=30) with depressive symptoms. There is evidence that catecholamines have an important role in the rewarding and withdrawal effects of tobacco smoking, and monoamine oxidase inhibitors (MAOIs) which augment catecholamine (i.e. dopamine, norepinephrine) function may be helpful in attenuating nicotine craving and withdrawal symptoms in nicotine dependent smokers. Thus, the selective MAO-B inhibitor selegiline may be helpful as a pharmacologic adjunct for smoking cessation. The proposed study would be a 6 week trial in nicotine-dependent smokers which will compare selegiline (10 mg daily; n=15) versus placebo (n=15) treatments on smoking cessation outcomes. Subjects would be inducted onto 10 mg/day of selegiline (5 mg po bid) or matching placebo (twice daily) over a two week period prior to the "quit date" at the beginning of Week 1. All subjects would receive brief weekly sessions of smoking cessation counseling consistent with AHCPR smoking cessation guidelines. The primary outcome measures include 1 week post-quit (Week 2) and endpoint (Week 6) smoking abstinence rates, and continuous smoking abstinence during the last four weeks of the trial. Secondary outcomes measures include treatment retention, depressive symptoms, nicotine withdrawal symptoms, weight change, plasma cotinine levels, expired breath carbon monoxide (CO) levels and urinary catecholamine excretion. Data analyses to compare groups will focus of an intention-to-treat sample and will utilize Chi square 2x2 contingency tables for smoking abstinence rates, repeated measures analysis of variance (ANOVA) models for continuous outcome measures (i.e. depression and nicotine withdrawal ratings, CC, plasma cotinine and urinary catecholamines) and Kaplan-Meir survival analysis for treatment retention. Results from this pilot study would be used to calculate an effect size for planning a larger controlled trial if results from this pilot study appear promising. We predict that selegiline will be superior to placebo for smoking cessation in nicotine dependent smokers on both primary and secondary outcome measures.